E-131 A time resolved 3D DSA protocol to evaluate aneurysmal flow following flow diversion

Introduction Time resolved three-dimensional angiography (4D DSA) was developed initially to investigate parameters related to the flow in arterio-venous malformations (AVMs). We have extended this protocol to evaluate flow before and after placement of a flow diverter for treatment of an intracranial aneurysm. Here we evaluate a prototype for 3D iFlow using 4D DSA imaging. Methods In this study, 4D DSA angiographic imaging (6 s syngo Dyna4D, Siemens Healthineers AG, Forchheim, Germany) was performed on 13 patients before and after receiving a pipeline (Medtronic, USA) across a known intracranial aneurysm. 4D DSA imaging was acquired before a pipeline was placed and after deployment of a pipeline on the same day using a constant flow rate of 3 ml/sec and 21 cc of contrast. 3D iFlow information was extracted using prototype software from the imaging and 3 bolus arrival time definitions were evaluated. Results Using three separate reconstruction protocols for 3D iFlow the flow proximal to the aneurysm and distal to the aneurysm showed similar average bolus arrival times (table 1). The bolus arrival time was then measured at a point just distal to the aneurysm being treated and within the aneurysm itself (table 2). The RECON 1 protocol appeared to most reliably demonstrate slowed contrast inflow into the aneurysm post deployment of the Pipeline device. Conclusion The 3D iFlow information obtained using 4D DSA imaging can provide clinicians information on the amount of flow pre and post deployment of a pipeline device for treatment of an intracranial aneurysm. This information could be useful to model aneurysm treatment and time to obliteration when utilizing pipeline flow diversion for the treatment of intracranial aneurysms. Continued work to refine protocols and software are needed to implement into clinical care. Disclaimer This product is under development and not commercially available. Its future availability cannot be ensured. Disclosures N. Khan: None. J. DiNitto: 5; C; Siemens. A. Birkhold: 5; C; Siemens. A. Arthur: None. C. Nickele: None. D. Hoit: None. V. Inoa: None. L. Elijovich: None.